Guayusa Extract on Exercise Training

Ability of Organic Guayusa Extract to Augment Desire to Train, Training Load, and Cardiometabolic Function in Physically Active Women Performing A High Intensity Exercise Training Program

Guayusa extract is a caffeinated Amazonian 'super-leaf' belonging to the holly species that contains a very unique blend of polyphenol antioxidants and caffeine (~20% caffeine, 30% chlorogenic acids, 5% catechins). It is also remarkably low in tannins which are responsible for the bitter taste found in most teas - giving it a sweet flavor profile. As such, it is marketed as an ingredient that can help support energy and performance with potential health-related benefits due to its antioxidant properties. Indeed, ingredients such as these are often consumed by individuals prior to exercise in order to help improve exercise performance, or otherwise to support health-related goals. Whereas several studies have suggested that caffeine and chlorogenic acid consumption may improve performance, mood, and concentration, and some evidence in animals have linked catechin consumption to improved health outcomes, no studies have previous studied whether guayusa extract supplementation helps to support exercise performance in humans. In this study, we will test the whether dietary supplementation with the botanical organic guayusa extract helps support (1) the desire to exercise and exercise performance throughout a 6-week high intensity exercise training program, and thus (2) helps support the physiological adaptations (including body composition, fasting metabolic biomarkers, blood pressure and heart rate, submaximal and maximal exercise performance and fuel metabolism, and changes in the gut microbiome/mycobiome) to a 6-week high intensity exercise training program.

Question 1: Does organic guayusa extract supplementation support the desire to train and training load in physically-active women performing a high-intensity exercise training program?

Question 2: Does organic guayusa extract supplementation support physiological adaptation to exercise (including body composition, fasting metabolic biomarkers, blood pressure and heart rate, submaximal and maximal exercise performance and fuel metabolism, and changes in the gut microbiome/mycobiome) in physically-active women performing a high-intensity exercise training program?

Study Overview

• Status: Completed
• Conditions: Exercise Training; Physical Exertion; Desire to Exercise
• Intervention / Treatment: Dietary supplement: Organic Guayusa Extract; Dietary supplement: Placebo

• Study Type: Interventional
• Enrollment (Actual): 57
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Iowa
    • Iowa City, Iowa, United States, 52242
      • Integrative Laboratory of Applied Physiology and Lifestyle Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Females
• 18-45 years, inclusive
• Physically active >=150 min/wk Moderate Intensity or >=75 min/wk Vigorous Intensity PA) for >=3 months
• BMI < 35 kg/m2
• Otherwise healthy and ready to participate in an exercise program as indicated by responses on the 2021 Physical Activity Readiness Questionnaire Plus (PAR-Q+)
• Habitual caffeine consumption <=200 mg/day OR 2-week washout of current caffeine usage prior to participation
• No current dietary supplementation OR 2-week washout of current supplement usage prior to participation

Exclusion Criteria:

• Current injury or illness that precludes exercise participation
• Current nicotine or cannabis use
• Use of prescription ADD/ADHD, anti-depressant, or other central acting medication, or previously diagnosed ADD/ADHD, clinically depressed, or generalized anxiety disorder
• Current taking prescription stimulants (i.e., Adderall, Ritalin, Vyvanse, etc.)
• Participants with a history of metabolic, hepatorenal, musculoskeletal, autoimmune, or neurologic disease; or currently taking thyroid, hormonal, hyperlipidemic, hypoglycemic, anti-hypertensive, anti-inflammatory, or anti-coagulant medications.
• Treated for Metabolic Syndrome or having been clinically diagnosed with, or taking medication for a cardiometabolic-disorder (e.g., Pre-diabetes, Type II diabetes, high blood pressure, obesity, hypercholesterolemia, etc.)
• Currently pregnant or lactating
• Diagnosed allergy to any ingredient present within the study treatments
• Current competitive NCAA athlete
• Inability or unwillingness to comply with the controls and conditions of the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Organic Guayusa Extract + High Intensity Exercise; Participants will consume an organic guayusa extract supplement that contains caffeine and antioxidants each day for 6 weeks while completing the exercise training program on 3 days/week. On days that participants exercise, they will consume the supplement 30-60 minutes before exercise training. On days they do not exercise, they will consume the capsules upon waking.	Dietary supplement: Organic Guayusa Extract; Supplementation: Participants will supplement daily with organic guayusa extract, which is a caffeinated Amazonian 'super-leaf' belonging to the holly species that contains a very unique blend of polyphenol antioxidants and caffeine (~20% caffeine, 30% chlorogenic acids, 5% catechins) during 6 weeks of high intensity exercise training. Investigators and participants will be blinded to condition.
Placebo Comparator: Placebo + High Intensity Exercise; Participants will consume a placebo consisting of maltodextrin each day for 6 weeks while completing the exercise training program. The placebo will be provided in capsule identical in appearance to the active supplement. On days that participants exercise, they will consume the placebo 30-60 minutes before exercise training. On days they do not exercise, they will consume the capsules upon waking.	Dietary supplement: Placebo; Participants will supplement daily with placebo (maltodextrin). Investigators and participants will be blinded to condition.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Desire to Exercise	Desire to Exercise will be assessed Primarily via the Assessment of Exercise Readiness using a 41-item Exercise Readiness Questionnaire.	Throughout 6-week training period.
Exercise Adherence	Exercise training session adherence will be assessed across all exercise training sessions as a primary quantitative indicator of desire to exercise. Adherence will be assessed as the actual number of completed exercise sessions among participants in each group relative (i.e., percent, %) to the number of total planned exercise sessions. Group differences in session adherence will be compared by chi squared tests.	Throughout 6-week training period.
Exercise Training Load	Resistance Exercise Training Volume (normalized to bodyweight) will be quantified in each resistance training workout (2x/week) and used as a quantitative indicator of exercise performance/effort.	Throughout 6-week training period.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Desire to Exercise Secondary Measures	Secondary assessments of Desire to Exercise will include visual analog scales (range 0 - 50, with 0 indicating lower desire and 50 indicating higher desire) used to assess readiness immediately before exercise sessions to "exercise right now", to "invest physical energy right now" and to "invest mental energy right now".	Throughout 6-week training period.
Exercise Training Performance	Secondary assessments of exercise training performance will include performance during a) a weekly airbike interval exercise session (Avg W), b) a weekly 500 m row (time to completion, Avg W), and c) the time (min) taken to complete the weekly metabolic conditioning workout.	Throughout 6-week training period.
VO2peak	VO2peak will be assessed during a ramp test on a electronically-braked cycle ergometer performed to volitional exhaustion with pulmonary gas exchange analysis.	baseline, <7 days after completing the intervention
Submaximal Exercise Fat Oxidation	Submaximal Exercise Fat Oxidation (%) will be assessed during exercise at a fixed power (i.e., 75W) on an electronically-braked cycle ergometer with pulmonary gas exchange analysis.	baseline, <7 days after completing the intervention
Submaximal Exercise Blood Pressure	Submaximal Systolic and Diastolic Exercise Blood Pressure (mmHg) will be assessed during exercise at a fixed power (75W) on an electronically-braked cycle ergometer.	baseline, <7 days after completing the intervention
Fasting metabolic biomarkers	Total cholesterol, HDL-cholesterol, LDL-cholesterol, non-HDL cholesterol, triglycerides, glucose, insulin, c-peptide, GLP-1, GIP	baseline, <7 days after completing the intervention
Fasting total cholesterol	Total cholesterol will be assessed from a fasting blood sample.	baseline, <7 days after completing the intervention
Fasting HDL-cholesterol	HDL-cholesterol will be assessed from a fasting blood sample.	baseline, <7 days after completing the intervention
Fasting non-HDL cholesterol	Non-HDL cholesterol will be assessed from a fasting blood sample.	baseline, <7 days after completing the intervention
Fasting triglycerides	Triglycerides will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting Glucose	Glucose will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting insulin	insulin will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting c-peptide	Fasting c-peptide will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting GLP-1	Fasting GLP-1 will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting GIP	Fasting GIP will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting IL-6	IL-6 will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting IL-10	IL-10 will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting TNFa	TNFa will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting triiodothyronine (T3)	Triiodothyronine (T3) will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting thyroxine (T4)	Thyroxine (T4) will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting Progesterone	Progesterone will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting Testosterone	Testosterone will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting Estrogen	Estrogen will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting Cortisol	Cortisol will be assessed from a fasting blood sample	baseline, at 1 week during the intervention, <7 days after completing the intervention
Fasting Adiponectin	Adiponectin will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting Leptin	Leptin will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting Adipsin	Adipsin will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting Lipocalin	Lipocalin will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting Plasminogen activator inhibitor-1 (PAI-1)	Plasminogen activator inhibitor-1 (PAI-1) will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention
Fasting Resistin	Resistin will be assessed from a fasting blood sample	baseline, <7 days after completing the intervention

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rating of Perceived Exertion	RPE will be assessed following each exercise session to determine subjective effort for each session on a scale of 1-10, where 1 is lowest perceived effort (e.g., rest) and 10 is greatest perceived effort.	Throughout 6-week training period.

Collaborators and Investigators

• Sponsor: Nathaniel Jenkins

Study record dates

Study Major Dates

• Study Start (Actual): September 5, 2022
• Primary Completion (Actual): November 18, 2022
• Study Completion (Actual): November 18, 2022

Study Registration Dates

• First Submitted: March 24, 2023
• First Submitted That Met QC Criteria: April 6, 2023
• First Posted (Actual): April 19, 2023

Study Record Updates

• Last Update Posted (Actual): April 19, 2023
• Last Update Submitted That Met QC Criteria: April 6, 2023
• Last Verified: April 1, 2023

More Information

Terms related to this study

• Other Study ID Numbers: 202110443

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No